The present invention relates to a stretcher for use in a hospital or other health care facility, and particularly to a procedural stretcher including an articulated patient support having a movable section that can be moved by a drive mechanism. More particularly, the present invention relates to a stretcher having a drive mechanism including both an automatic mechanized drive assembly and a manual hand-operated drive assembly, each of which operate to move the movable section of the patient support.
Stretchers for transporting a patient in a hospital or other health care facility from one location to another are well known. Conventional stretchers may include an articulated patient-support deck having sections that can be adjusted to adjust the position of the patient. See, for example, U.S. Pat. Nos. 4,723,808 to Hines and 4,629,242 to Schrager, each of which discloses a patient support deck having a movable head section.
Many stretchers having movable patient-support sections include hand-operated assemblies that can be manually operated to adjust the position of the patient-support sections. For example, each of the Hines '808 patent and the Schrager '242 patent discloses a stretcher having a shaft coupled to a movable patient-support section and a hand crank for rotating the shaft to adjust the position of the movable patient-support section.
Hospital beds are generally less mobile than stretchers and typically are not used to transport patients between locations, but rather remain at a single location during use when a patient rests on the bed. Hospital beds may also be provided with articulated patient supports having sections that can be adjusted to place the patient resting on the bed in a variety of positions. See, for example, U.S. Pat. Nos. 5,444,880 to Weismiller et al.; 4,751,754 to Bailey et al.; 4,559,655 to Peck; and 3,436,769 to Burst; all of which are assigned to the assignee of the present invention, and see also, U.S. Pat. Nos. 5,423,097 to Brule et al. and 4,545,084 to Peterson. Each of these references discloses a hospital bed having articulated head, seat, thigh, and foot sections, at least one of which can be moved to adjust the position of the patient.
Some hospital beds having articulated patient-support sections have manual hand-operated assemblies that can be operated to adjust the position of the movable sections and some have mechanized assemblies that can be actuated to adjust the position of the movable sections. For example, each of the Brule et al. '097 patent and the Peterson '084 patent discloses a hospital bed having a manually rotated hand crank to raise and lower the movable sections of the bed. See also the Weismiller et al. '880 patent, the Bailey et al. '754 patent, the Peck '655 patent, and the Burst '769 patent which are assigned to the assignee of the present invention, and see U.S. Pat. No. 5,329,657 to Bartley et al, each of which discloses a hospital bed having an electric motor that can be activated to raise and lower the movable sections of the bed.
Hospital beds having mechanized assemblies that adjust the movable sections may include patient control buttons that are accessible by the patient for actuating the mechanized assemblies to adjust the positions of the sections to a desired position. In addition, such hospital beds may include limit switches to limit the ranges of motion of designated sections and lockout switches that can be activated by a caregiver to deactivate the patient control buttons. See, for example, U.S. Pat. Nos. 4,044,286 to Adams et al. and 3,913,153 to Adams et al., both of which are assigned to the assignee of the present invention and both of which disclose the use of a limit switch limiting the movement of the movable sections and a lockout switch that can be moved to a position preventing an electric motor from being actuated by the patient control buttons.
Hospital beds having a movable head section may include a manually operated quick-release handle for rapidly lowering the head section, for example, when a patient goes into cardiac arrest, so that cardiopulmonary resuscitation (CPR) can be administered to the patient. See, for example, the Weismiller et al. '880 patent, the Peck '655 patent, and U.S. Pat. No. 5,129,116 to Borders et al., all of which are assigned to the assignee of the present invention, and see U.S. Pat. No. 5,329,657 to Bartley et al. Each of these references discloses a mechanism that can be actuated to rapidly lower the head section to a flat position.
What is desired is a stretcher having a drive mechanism including both a mechanized drive and a hand-operated drive, each of which can be used to adjust the same movable section of the patient-support deck. The mechanized drive should be usable to move the movable section when the stretcher is generally stationary and receiving power from an external power source. The hand-operated drive should be manually actuatable to move the movable section both when the stretcher is connected to the external power source and when the stretcher is disconnected from the external power source. Such a stretcher should also include patient control buttons accessible by the patient to actuate the mechanized drive and caregiver control switches accessible by a caregiver to actuate the mechanized drive. Additionally, the stretcher should include hand cranks that are accessible by the caregiver to manually actuate the hand-operated drive. The stretcher should also include a CPR mechanism having a CPR release handle that, when actuated, allows a head section of a patient-support deck to quickly lower to a generally horizontal table position.
According to the present invention, a stretcher is provided having a frame and a patient-support deck mounted on the frame. The patient-support deck includes longitudinally spaced-apart sections. At least one of the sections is a movable section that is coupled to the frame for pivoting movement relative to the other deck sections between a raised position and a lowered position through an intermediate position therebetween. The stretcher includes a drive mechanism that, when actuated, moves the movable section relative to the other deck sections. The drive mechanism is coupled to the frame and coupled to the movable section.
The drive mechanism includes a hand-operated drive for moving the movable section between the raised position and the lowered position and a mechanized drive for moving the movable section between the raised position and the lowered position. Control buttons are coupled to the mechanized drive and the control buttons are engageable to activate the mechanized drive to lower the movable section from the raised position to the lowered position and to raise the movable section from the lowered position only to the intermediate position. The control buttons are configured so that the mechanized drive does not activate to move the movable section from the intermediate position toward the raised position in response to engagement of the control buttons.
In preferred embodiments, the stretcher includes a frame and a patient-support deck having articulated head, seat, thigh, and foot sections mounted to the frame. The thigh section is coupled to the frame for pivoting movement between a raised position raising the knees of the patient and a lowered position. A thigh section actuator that extends and retracts is coupled to the thigh section and to the frame. The thigh section actuator moves the thigh section between the raised position and the lowered position.
The head section is coupled to the frame for pivoting movement and is infinitely positionable between a generally vertical raised position and a generally horizontal lowered position through an intermediate position therebetween. A head section actuator that extends and retracts is coupled to the head section and to the frame. The actuator moves the head section between the raised position and the lowered position. However, movement of the head section relative to the thigh section is limited under certain circumstances to limit the extent to which the patient can close the angle defined between the head section and the thigh section. In addition, a CPR mechanism having a release handle is coupled to the head section actuator so that when the release handle is actuated, the head section quickly moves to the lowered position.
A head section motor is coupled to the head section actuator to drive the head section actuator and a thigh section motor is coupled to the thigh section actuator to drive the thigh section actuator. Patient control buttons are mounted on a side guard rail and coupled to each motor so that patient control buttons can be pressed to activate the motors. Caregiver control switches are mounted on the frame of the stretcher at a foot end of the stretcher away from the patient but accessible by the caregiver attending to the patient and are coupled to at least one of the motors so that caregiver control switches can be actuated to activate at least one of the motors. In addition, a pair of hand cranks are mounted on the frame of the stretcher at the foot end of the stretcher. One hand crank can be manually rotated to drive the head section actuator to move the head section between the raised and lowered positions and the other hand crank can be manually rotated to drive the thigh section actuator to move the thigh section between the raised and lowered positions.
The patient control buttons can be pressed to operate the motors to drive the actuators and move the thigh section between the raised and lowered positions, move the head section from the raised position to the lowered position, and move the head section from the lowered position to the intermediate position. However, the patient control buttons are configured so that the patient control buttons do not operate the motors to move the head section toward the raised position past the intermediate position. Thus, the extent to which the patient control buttons can be used to activate the head section motor to move the head section toward the raised position, closing the angle between the head section and the thigh section, is limited.
The caregiver control switches operate the head section motor to move the head section to desired positions within the full range of motion of the head section between the raised and lowered positions. Additionally, the hand cranks also operate the head and thigh section actuators to move the head and thigh sections to desired positions within the full range of motion of the head and thigh sections.
Thus, the head and thigh section motors provide a mechanized drive to drive the actuators and adjust the position of the head and thigh sections, respectively. In addition, the hand cranks provide a hand-operated drive to drive the actuators and adjust the position of the head and thigh sections. The caregiver can use both the mechanized drive and the hand-operated drive to adjust the position of the head and thigh sections through the full range of motion of the head and thigh sections. The patient can use only the mechanized drive to adjust the position of the head and thigh sections and can only raise the head section up to the intermediate position. However, the patient can use the mechanized drive to lower the head section from any position down to the lowered position when the stretcher receives power from an external power source.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of a preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.